The present invention is directed generally to apparatus for representing a plurality of positions of an element in digital logic form and more particularly to such an apparatus adapted for use with a joystick-type of shift lever arrangement for providing a digital logic representation of the position of a shift lever relative to a given shift pattern.
Joystick-type control levers are utilized in many applications, including relatively simple video game devices, as well as relatively more demanding machinery control applications. Such control applications may include the control of industrial machinery and/or gear shift levers for both off-road and on-road vehicles.
In such industrial and vehicular applications, the shift levers must be very rugged and reliable in operation over a relatively long service life. These relatively rugged assemblies must continue to operate reliably in spite of adverse environmental conditions which might be encountered, whether it be on the factory floor, or in on-road or off-road vehicular applications.
In particular, in mechanized farm equipment, such joystick-type of shift or other control levers must operate in a hostile environment. In the agricultural applications, this generally includes use in vehicles such as tractors and harvesters which transverse fields during plating, cultivation, fertilizing and harvesting operations. In these operations, considerable dirt, dust and the like is encountered in the field or even created by operation the machinery itself. Moreover, various pesticides, herbicides and fertilizer materials can be corrosive and/or abrasive, causing premature wear and failure of both mechanical and electrical or electronic components of such control systems.
In this latter regard, the assignee of the present application has also developed a number of novel electronic and/or microcomputer-based control systems for various agricultural or other on-road and off-road vehicles and/or other machinery applications. Accordingly, it is also desirable to provide a joystick controller which is capable of simply and readily interfacing with existing control systems to provide an easy-to-use digital logic representation of the position of the shift lever with respect to a given shift pattern.